/*
* Conditions Of Use 
* 
* This software was developed by employees of the National Institute of
* Standards and Technology (NIST), an agency of the Federal Government.
* Pursuant to title 15 Untied States Code Section 105, works of NIST
* employees are not subject to copyright protection in the United States
* and are considered to be in the public domain.  As a result, a formal
* license is not needed to use the software.
* 
* This software is provided by NIST as a service and is expressly
* provided "AS IS."  NIST MAKES NO WARRANTY OF ANY KIND, EXPRESS, IMPLIED
* OR STATUTORY, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTY OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT
* AND DATA ACCURACY.  NIST does not warrant or make any representations
* regarding the use of the software or the results thereof, including but
* not limited to the correctness, accuracy, reliability or usefulness of
* the software.
* 
* Permission to use this software is contingent upon your acceptance
* of the terms of this agreement
*  
* .
* 
*/
/*******************************************************************************
* Product of NIST/ITL Advanced Networking Technologies Division (ANTD).        *
*******************************************************************************/
package gov.nist.javax.sip.header;

import java.util.*;
import java.text.ParseException;
import javax.sip.header.*;

/**
 * the UserAgent SIPObject. 
 *
 * @author Olivier Deruelle <br/>
 * @version 1.2 $Revision: 1.7 $ $Date: 2008/07/30 14:36:06 $
 *
 * 
 *
 */
public class UserAgent extends SIPHeader implements UserAgentHeader {

	/**
	 * Comment for <code>serialVersionUID</code>
	 */
	private static final long serialVersionUID = 4561239179796364295L;
	/** Product tokens.
	*/
	protected List productTokens;

	/**
	 * Return canonical form.
	 * pmusgrave - put a space between products (preserves format of header)
	 * @return String
	 */
	private String encodeProduct() {
		StringBuffer tokens = new StringBuffer();
		ListIterator it = productTokens.listIterator();

		while (it.hasNext()) {
			tokens.append((String) it.next());
			
		}
		return tokens.toString();
	}

	/** set the productToken field
	 * @param pt String to set
	 */
	public void addProductToken(String pt) {
		productTokens.add(pt);
	}

	/**
	 * Constructor.
	 */
	public UserAgent() {
		super(NAME);
		productTokens = new LinkedList();
	}

	/** Encode only the body of this header.
	*@return encoded value of the header.
	*/
	public String encodeBody() {
		return encodeProduct();
	}

	/**
	* Returns the list value of the product parameter.
	*
	* @return the software of this UserAgentHeader
	*/
	public ListIterator getProduct() {
		if (productTokens == null || productTokens.isEmpty())
			return null;
		else
			return productTokens.listIterator();
	}

	/**
	 * Sets the product value of the UserAgentHeader.
	 *
	 * @param product - a List specifying the product value
	 * @throws ParseException which signals that an error has been reached
	 * unexpectedly while parsing the product value.
	 */
	public void setProduct(List product) throws ParseException {
		if (product == null)
			throw new NullPointerException(
				"JAIN-SIP Exception, UserAgent, "
					+ "setProduct(), the "
					+ " product parameter is null");
		productTokens = product;
	}

	public Object clone() {
		UserAgent retval = (UserAgent) super.clone();
		if (productTokens != null)
			retval.productTokens = new LinkedList (productTokens);
		return retval;
	}

}
/*
 * $Log: UserAgent.java,v $
 * Revision 1.7  2008/07/30 14:36:06  mranga
 * Issue number:
 * Obtained from:
 * Submitted by:  mranga
 * Reviewed by:   mranga
 * Fix minor issue in encoding of user-agent header.
 *
 * Revision 1.6  2006/10/12 11:57:55  pmusgrave
 * Issue number:  79, 80
 * Submitted by:  pmusgrave@newheights.com
 * Reviewed by:   mranga
 *
 * Revision 1.5  2006/07/13 09:01:48  mranga
 * Issue number:
 * Obtained from:
 * Submitted by:  jeroen van bemmel
 * Reviewed by:   mranga
 * Moved some changes from jain-sip-1.2 to java.net
 *
 * CVS: ----------------------------------------------------------------------
 * CVS: Issue number:
 * CVS:   If this change addresses one or more issues,
 * CVS:   then enter the issue number(s) here.
 * CVS: Obtained from:
 * CVS:   If this change has been taken from another system,
 * CVS:   then name the system in this line, otherwise delete it.
 * CVS: Submitted by:
 * CVS:   If this code has been contributed to the project by someone else; i.e.,
 * CVS:   they sent us a patch or a set of diffs, then include their name/email
 * CVS:   address here. If this is your work then delete this line.
 * CVS: Reviewed by:
 * CVS:   If we are doing pre-commit code reviews and someone else has
 * CVS:   reviewed your changes, include their name(s) here.
 * CVS:   If you have not had it reviewed then delete this line.
 *
 * Revision 1.3  2006/06/19 06:47:27  mranga
 * javadoc fixups
 *
 * Revision 1.2  2006/06/16 15:26:28  mranga
 * Added NIST disclaimer to all public domain files. Clean up some javadoc. Fixed a leak
 *
 * Revision 1.1.1.1  2005/10/04 17:12:35  mranga
 *
 * Import
 *
 *
 * Revision 1.3  2005/04/16 20:38:51  dmuresan
 * Canonical clone() implementations for the GenericObject and GenericObjectList hierarchies
 *
 * Revision 1.2  2004/01/22 13:26:30  sverker
 * Issue number:
 * Obtained from:
 * Submitted by:  sverker
 * Reviewed by:   mranga
 *
 * Major reformat of code to conform with style guide. Resolved compiler and javadoc warnings. Added CVS tags.
 *
 * CVS: ----------------------------------------------------------------------
 * CVS: Issue number:
 * CVS:   If this change addresses one or more issues,
 * CVS:   then enter the issue number(s) here.
 * CVS: Obtained from:
 * CVS:   If this change has been taken from another system,
 * CVS:   then name the system in this line, otherwise delete it.
 * CVS: Submitted by:
 * CVS:   If this code has been contributed to the project by someone else; i.e.,
 * CVS:   they sent us a patch or a set of diffs, then include their name/email
 * CVS:   address here. If this is your work then delete this line.
 * CVS: Reviewed by:
 * CVS:   If we are doing pre-commit code reviews and someone else has
 * CVS:   reviewed your changes, include their name(s) here.
 * CVS:   If you have not had it reviewed then delete this line.
 *
 */
